When cleaning re-usable bottles before they are filled again, these bottles are soaked in baths and are sprayed outside and especially inside at spraying stations. Even new bottles frequently are sprayed on their insides before being filled. In inside spraying, a liquid jet pointed at the inside of the bottle and is expected to reach all of its zones and rinse them. Affixed dirt is to be removed reliably if at all possible and to be rinsed out. The bottles are suspended above a nozzle array which sprays them from below so that the liquid can drain from the bottle inside after spraying.
Nozzle systems of the above kind comprise a rotationally driven nozzle unit in which the spray jet or stream follows the mouth of a moving bottle over a specified angular range. This design offers the advantage that the bottles can be continuously moved inside a bottle cleaning machine and are sprayed within the pivot range of the jet for an appreciable time. Another essential advantage is that the spray jet enters the bottle at different angles within the nozzle's pivot angle and hence impinges upon different wall zones of the bottle inside. Accordingly, there is expected to be intensive cleaning at different jet impact points.
Such nozzle designs of the initially cited kind are known in the state of the art. Illustratively, the nozzle unit pivots together with the nozzle pipe, for instance in a to-and-fro swinging motion. A design is known from the German patent 24 02 630, wherein the nozzle unit pivots relative to the nozzle pipe, opposite ends of the bore alternatingly pointing outward toward the bottle.
In the known nozzle systems of the foregoing kind, the nozzle bores are perpendicular to the axis of nozzle rotation and thereby generate a spray jet pivoting in the plane perpendicular to the axis of rotation. This entails the drawback that the jet impact points in the bottle all are located on a central plane through the axis of rotation of the bottle. During the pivoting motion of the jet, therefore, the impact points inside the bottle form a path moving up one side wall, across the center of the bottle base and down again on the other side of the bottle. There is, thus, insufficient rinsing in the lateral zones of the bottle away from that plane.